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Play 2.0.2 and Scala Mapping Form to Case Class with List of Objects

Hi guys.. Here I'm going to explain you how to map play form data to a Case class object. Speciality of this case class is it contains list of object as a field. Here is my class Course (Course.scala). Assume that Course can contain number of Subjects.
Course ------------> Subjects 
case class Course(
  id: ObjectId = new ObjectId,
  var name: String = "",
  var description: String = "",
  var price: Int = 0,
  var subjects: List[Subject] = List.empty ){
}
 
case class Subject(
  var name: String = "", 
  var description: String = ""
   ){}



//This line is for database table creation
//I'm Using MongoDB so table will be created at runtime
object Course extends ModelCompanion[Course, ObjectId] {
  val collection = mongoCollection("course") //table name course
  val dao = new SalatDAO[Course, ObjectId](collection = collection) {}
}

Now I'm going to map this object to play form (play.api.mvc.Form). First I have Course and as a field of that I have a List of Subjects. Here inside the Controller This is mapped like this. Only mapping method is displayed 

def courseForm(implicit request: RequestHeader): Form[Course] = Form(
    mapping(
      "id" -> nonEmptyText,
      "name" -> nonEmptyText,
      "description" -> nonEmptyText,
      "price" -> nonEmptyText,
      "subjects" -> play.api.data.Forms.list
                  (mapping(
                  "name" -> nonEmptyText,
             "description" -> nonEmptyText)((
            name,
            description) => Subject(
            name = name,
            description = description
            ))(
            sub => Some(
               sub.name,
               sub.description
                   )))
                        )((
     id,
                   name,
                   description,
                   price,
                   subjects
            ) => Course(
         id = new ObjectId(id),
                name = name,
         description = description,
         price = toInt,
         subjects = subjects.toList
          ))(
        course => Some(
            course.id.toString,
            course.name,
            course.description,
            course.price.toString,
            course.subjects
           )))

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